The present invention relates to power supplies and more particularly to power supplies capable of supplying power to a variety of alternative devices.
There continues to be dramatic growth in the use of portable electronic devices, such as laptops, personal digital assistants, cellular phones, smart phones and portable media players. Although a variety of standards have been developed for providing wireless communication with electronic devices, many of these devices continue to be plagued by the need for a power supply that is connected to the electronic device by a cord. Typically, each power supply includes a power adapter for converting AC mains power into the DC power required by the device along with cords for connecting the input of the adapter to a wall outlet and the output of the adapter to the electronic device. In some cases, a plug extends from the adapter so that the adapter plugs directly into a wall outlet and only a single cord from the adapter to the electronic device is required (See FIG. 1). Power adapters (often referred to as “bricks”) are relatively heavy and occupy a large amount of space. Conventional power supply systems suffer from a variety of disadvantages. For example, the power supply with adapter and associated cords is a burden to use, store and carry around as needed. In use, cords create an unsightly and often unmanageable mess. Further, when connected, cords impede device mobility. With multiple portable devices, a user may be required to carry around multiple power supplies, including multiple power adapters and multiple cord sets. This only compounds the problem.
In an effort to reduce the problem, “universal” power supplies have been developed. Efforts to provide a universal power solution are complicated by a variety of practical difficulties. One of these difficulties arises because different portable electronic devices have different power requirements. A conventional universal power supply includes a single power adapter that is capable of providing power to multiple devices. For example, a conventional universal power supply is illustrated in FIG. 2. In this embodiment, the power supply includes a power adapter having multiple power outlet ports. The power adapter is configured to supply a predetermined amount of power to each outlet port. Various electronic devices, such as laptops and smart phones can be connected to the power adapter using conventional cords. Although a marked improvement, this solution still requires a separate cord for each device connected to the power supply. Further, typical solutions require the electronic devices to be preconfigured to accept the predetermined power output by the power supply.
As an alternative to corded power supply solutions, there has recently been dramatic growth in the pursuit of wireless power solutions. Wireless power supply systems eliminate the need for power cords and therefore eliminate the many inconveniences associated with power cords. For example, wireless power solutions can eliminate: (i) the need to retain and store a collection of power cords, (ii) the unsightly mess created by cords, (iii) the need to repeatedly physically connect and physically disconnect remote devices with cords, (iv) the need to carry power cords whenever power is required, such as recharging, and (v) the difficulty of identifying which of a collection of power cords is used for each device.
The introduction of wireless power solutions has in one respect made power management across multiple devices more complicated—at least in the short term. For example, a user that has both wirelessly powered/charged devices and devices that are powered/charged using wires will be required to carry both wired and wireless power supplies. Even if the user has invested in a universal power supply for all of the users wired devices, a separate wireless power supply will be required.